Mark Zuckerberg took the stage Monday night at San Francisco's Yerba Buena Center for the Arts to give an opening statement before a screening of the documentary film Documented. It was a rare public appearance for the Facebook CEO, in which he put a personal touch to his position on immigration reform.

The film, by Pulitzer-Prize winning journalist and self-identified "undocumented American" Jose Antonio Vargas, explores the plight of undocumented immigrants in the U.S. and their children--many of whom arrived in the country during early childhood and would benefit from the DREAM Act, which seeks to provide a path to citizenship for younger undocumented immigrants.

In other words, the film addresses a portion of the immigrant population not previously endorsed so much by Silicon Valley: Low-skill workers. And this was Zuckerberg's point. When lobbyists speak about immigration, he said, they act as if they are two seperate issues: Visas that apply to highly skilled technology or engineering professionals, and visas that apply to low-skill laborers.

"Anyone who knows a dreamer, knows they're not [two issues]," said Zuckerberg. The children of immigrants become the next generation of entrepreneurs, he contended.

Zuckerberg said he was inspired to get involved in the movement for reform (he is the co-founder of FWD.us, an immigration advocacy group) after doing exactly that--meeting a group of dreamers, or undocumented children, at the middle school in Menlo Park where he taught a weekly course on entrepreneurship.

When asking his students what challenges faced them and their future, Zuckerberg said he was shocked by one child's answer.

"He said, 'I'm not sure I'm going to be able to go to college because I'm undocumented,'" Zuckerberg said. So the entrepreneur decided to take an informal survey. How many of the students were undocumented?

"Almost half of them," he said.

Vivek Wadhwa, a Silicon Valley entrepreneur and VP of Innovation at the tech accelerator Singularity University, said that Zuckerberg's presence at the screening--and his personal identification with the issue--was "crucial" to establishing Facebook as a sincere supporter of reform. Wadhwa, who also writes a column for The Washington Post, has been a vocal critic of FWD.us and Zuckerberg's involvement in the movement.

"No cause is worth selling your soul for," Wadhwa has said of FWD.us's controversial presence in Washington, D.C. He criticized the movement for "coming out of nowhere and buying up politicians."

For Wadwha, who rescheduled a business flight to attend, the screening marked a change in the organization's advocacy of immigration reform. What set the event appart for him: That Zuckerberg himself was speaking, as a representative of Facebook, and that he was "talking about low skill workers--not just the [tech] community needs."

Wadwha told Inc. that he was pleased to see Facebook's presence as a vote of confidence to the movement, but acknowledged that the tech community has a long way to go if it wants to enact meaningful change surrounding immigration reform.